Propeller pull and thrust test device

Abstract

This invention discloses a propeller thrust and pull testing device applied to a turboprop engine. The turboprop engine includes a reduction gear, which includes a casing, a power turbine shaft, an input gear, a driven gear, and a propeller shaft. The input gear is located on the power turbine shaft, and the driven gear is located on the propeller shaft and meshes with the input gear. A first bearing and a second bearing are respectively installed between the two ends of the power turbine shaft and the casing. A third bearing for bearing radial force is installed between the rear end of the propeller shaft and the casing. A mounting structure is installed between the front end of the propeller shaft and the casing. A fourth bearing and a fifth bearing are respectively installed between the inner side of the mounting structure and the outer wall of the front end of the propeller shaft. The fourth bearing is used to bear axial force, and the fifth bearing is used to bear radial force. The testing device includes a first force-measuring ring located at the end of the fifth bearing facing the fourth bearing and a second force-measuring ring located at the end of the fourth bearing away from the fifth bearing. The first force-measuring ring tests the thrust, and the second force-measuring ring tests the thrust.

Description

Technical Field

[0001] This invention relates to the field of aero-engine testing technology, and in particular, to a propeller thrust and pull testing device. Background Technology

[0002] Shaft power is one of the main performance indicators of a turboprop engine. However, for turboprop aircraft, shaft power does not directly reflect the aircraft's power performance. Aircraft require specific propeller thrust inputs under different flight conditions to achieve optimal engine-flight matching performance, especially considering the negative thrust generated during propeller counter-rotation, which is closely related to flight safety. However, current conventional propeller thrust measurement methods are affected by factors such as airflow and transmission path, resulting in low measurement accuracy.

[0003] A typical turboprop engine mainly consists of a gearbox, compressor, turbine, and combustion chamber, such as... Figure 1 As shown. The gearbox is an important component of a turboprop engine. The power to the gearbox is input from the power turbine and output through the propeller.

[0004] Existing methods for measuring propeller thrust typically involve using the engine mounting strut system load measurement method during flight testing. Turboprop aircraft connect the engine mount with its dampers and the aircraft's load-bearing truss with its load-bearing frame via an engine linkage system. Engine power is transmitted to the aircraft through this linkage, and the load-bearing truss is mounted on the wing leading edge. Due to the unique structure of the linkage system, propeller thrust can be measured using strain gauges. Theoretically, by measuring the strain of the linkage system with strain gauges, the propeller thrust can be calculated. Based on the actual installation of the propeller and engine on the aircraft, and the theoretical stress conditions designed according to the linkage system, each strut can be considered a two-force member. However, considering that the aircraft is also moving while the propeller generates thrust, the engine is subjected to loads such as inertial forces (torque) and gyroscopic torques in addition to the main thrust and propeller torque, making the stress situation more complex. Although under ideal stress conditions, the connecting rod is only subjected to pure tension or compression, in reality, the rotation of the propeller will inevitably introduce other loads to the connecting rod, mainly the torque around the propeller axis, which makes the force transmission path of the strut more complex and the accuracy of the connecting rod method measurement is not high.

[0005] Existing propeller thrust measurement schemes are still based on the thrust measurement principle of a "dynamic-static frame-spring plate" structure test bench. They employ a ground-based test bench and a dynamic-static frame structure to measure propeller thrust and propeller force. Figures 3 to 4This paper describes the frame structure and stress conditions of a test bench for a certain type of turboprop engine with a propeller. The engine adopts a front-mounted, suspended installation. To meet the requirements for thrust measurement, the test bench uses a dynamic-static frame structure. The engine is mounted on the dynamic frame via a mounting bracket, and the dynamic frame is suspended from the static frame by four spring plates. Horizontally, the dynamic frame is constrained by four force sensors mounted on the static frame. Two force sensors in the intake direction restrict the forward movement of the dynamic frame (measuring propeller thrust), and two force sensors in the exhaust direction restrict the backward movement of the dynamic frame (measuring reverse propeller thrust). When the engine is operating, the spring plates only bear tension; the constraint force on the dynamic frame in the engine axial direction is negligible. Therefore, the thrust or thrust generated by the propeller is ultimately transmitted to the thrust or thrust sensors, allowing the measurement of the turboprop engine's thrust or thrust. The above describes the thrust measurement principle of the "dynamic-static frame-spring plate" structure test bench. However, the large frontal area of ​​the engine ground test bench and the propeller airflow severely affect the tensile force measurement results, resulting in large fluctuations in the tensile force measurement results. Furthermore, the test data differs greatly from the theoretical calculation values, and the cost of building the test structure is high. Summary of the Invention

[0006] This invention provides a propeller thrust and pull testing device to solve the technical problems of low accuracy and high cost in propeller thrust measurement structures.

[0007] According to one aspect of the present invention, a propeller thrust and pull testing device is provided, applied to a turboprop engine. The turboprop engine includes a reduction gear, which includes a casing, a power turbine shaft, an input gear, a driven gear, and a propeller shaft. The input gear is disposed on the power turbine shaft, and the driven gear is disposed on the propeller shaft and meshes with the input gear. A first bearing and a second bearing are respectively disposed between the two ends of the power turbine shaft and the casing. A third bearing for bearing radial force is disposed between the rear end of the propeller shaft and the casing. A mounting structure is disposed between the front end of the propeller shaft and the casing. A fourth bearing and a fifth bearing are respectively disposed between the inner side of the mounting structure and the outer wall of the front end of the propeller shaft. The fourth bearing is located between the bottom of the mounting structure and the fifth bearing. A predetermined radial clearance is provided between the fourth bearing and the inner wall of the mounting structure. The fourth bearing is used to bear axial force, and the fifth bearing is used to bear radial force. The testing device includes a first force-measuring ring disposed between the fifth bearing and the fourth bearing, and a second force-measuring ring disposed at the end of the fourth bearing away from the fifth bearing. The first force-measuring ring is used to test the thrust, and the second force-measuring ring is used to test the thrust.

[0008] As a further improvement to the above technical solution, the mounting structure includes a bearing bushing for being fitted into an end hole at the front end of the casing, the front end of the casing is provided with a stepped structure, and the bearing bushing is axially positioned and engaged with the stepped structure.

[0009] As a further improvement to the above technical solution, strain gauges are uniformly distributed circumferentially on the first force measuring ring, and strain gauges are uniformly distributed circumferentially on the second force measuring ring.

[0010] As a further improvement to the above technical solution, the testing device also includes a lead wire structure for leading the signal wire connected to the strain gauge to the outside of the housing.

[0011] As a further improvement to the above technical solution, the testing device also includes an anti-rotation structure distributed on the first force measuring ring and the second force measuring ring, used to limit the circumferential position of the first force measuring ring and the second force measuring ring.

[0012] As a further improvement to the above technical solution, the anti-rotation structure includes a first anti-rotation boss disposed on the end face of the first force-measuring ring facing one end of the fifth bearing, and a first mounting groove for embedding the first anti-rotation boss is provided on the fifth bearing. The anti-rotation structure also includes a second anti-rotation boss disposed circumferentially on the second force-measuring ring, and the second anti-rotation boss extends axially to both ends based on the second force-measuring ring. A second mounting groove for embedding the second anti-rotation boss is provided on the outer ring of the fourth bearing, and a third mounting groove for cooperating with the second anti-rotation boss is provided on the bearing bushing.

[0013] As a further improvement to the above technical solution, the lead wire structure includes a wire hole opened in the first force measuring ring, a first wire outlet groove opened in the outer wall of the fourth bearing, and a second wire outlet groove disposed in the outer wall of the second force measuring ring. The second wire outlet groove is disposed in the second anti-rotation boss, and the second mounting groove is integrated with the first wire outlet groove.

[0014] As a further improvement to the above technical solution, the outer end of the fifth bearing is provided with a mounting edge for engaging with the end face of the front end of the casing.

[0015] As a further improvement to the above technical solution, the third bearing and the fifth bearing are cylindrical roller bearings, and the fourth bearing is a four-point contact ball bearing, a deep groove ball bearing, or a spherical roller thrust bearing.

[0016] As a further improvement to the above technical solution, the inner ring of the fourth bearing, away from the fifth bearing, abuts against the end of the driven gear or against the shoulder of the propeller shaft, and the bottom of the bearing bushing and the outer ring of the fourth bearing, away from the fifth bearing, form a preset axial distance so that the second force measuring ring and the bottom of the bearing bushing have an axial gap.

[0017] The present invention has the following beneficial effects:

[0018] This testing device installs a third bearing at the rear support point of the propeller shaft. A mounting structure is used to install a fourth and fifth bearing at the front support point of the propeller shaft. The three support points work together to ensure that the radial force generated during propeller operation is borne solely by the third and fifth bearings at both the front and rear support points. The fourth bearing only bears the axial force and not the radial force. A first force-measuring ring and a second force-measuring ring are respectively installed at both ends of the outer ring of the fourth bearing. When a positive propeller thrust is applied, the force is transmitted through the propeller shaft and the inner ring of the fourth bearing to the outer ring of the fourth bearing, pressing the first force-measuring ring against the outer ring of the fifth bearing. The axial force borne by the fourth bearing is obtained by testing the strain of the first force-measuring ring under load. Conversely, when a negative propeller thrust is applied... At this time, the thrust is transmitted from the propeller shaft to the inner ring of the fourth bearing and then to the outer ring of the fourth bearing, pressing the second force measuring ring to the mounting structure. By measuring the strain of the second force measuring ring under load, the axial force borne by the fourth bearing is obtained. Since the reducer is a spur gear transmission structure, no additional axial force is generated during the meshing of the gear pair. Therefore, the axial force borne by the fourth bearing is the propeller thrust / thrust. Compared with the load measurement method of the engine mounting strut system and the method of building a ground test stand, this test device has higher testing accuracy and is not affected by environmental factors and flight airflow. The overall structure is simplified and does not require additional measurement structure. It can simultaneously measure the positive and negative thrust of the propeller, with high measurement accuracy and low cost.

[0019] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0020] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0021] Figure 1 This is a simplified structural diagram of a turboprop engine using existing technology;

[0022] Figure 2 It is a connecting rod assembly diagram for measuring the thrust of a turboprop engine using existing technology;

[0023] Figure 3 This is a side view of an existing engine test bench.

[0024] Figure 4 This is a front view of an existing engine test bench.

[0025] Figure 5 This is a schematic diagram of the internal structure of a turboprop engine reducer according to a preferred embodiment of the present invention;

[0026] Figure 6This is a schematic diagram of the assembly structure of the force measuring device according to a preferred embodiment of the present invention;

[0027] Figure 7 This is a schematic diagram of the structure of the fifth bearing according to a preferred embodiment of the present invention;

[0028] Figure 8 This is a schematic diagram of the structure of the first force-measuring ring according to a preferred embodiment of the present invention;

[0029] Figure 9 This is a schematic diagram of the structure of the fourth bearing according to a preferred embodiment of the present invention;

[0030] Figure 10 This is a schematic diagram of the structure of the second force-measuring ring according to a preferred embodiment of the present invention;

[0031] Figure 11 This is a schematic diagram of the bearing bushing according to a preferred embodiment of the present invention;

[0032] Figure 12 This is a schematic diagram of the propeller thrust transmission path according to a preferred embodiment of the present invention;

[0033] Figure 13 This is a schematic diagram of the propeller negative thrust transmission path according to a preferred embodiment of the present invention.

[0034] Legend:

[0035] 1. Spline; 2. Input gear; 3. Driven gear; 4. Propeller shaft; 5. Front casing; 501. Stepped structure; 6. Rear casing; 7. First bearing; 8. Second bearing; 9. Third bearing; 10. Fourth bearing; 101. Second mounting slot; 102. First cable outlet slot; 11. Fifth bearing; 111. First mounting slot; 112. Mounting edge; 12. Locking nut; 13. First force measuring ring; 131. First anti-rotation boss; 132. Cable through hole; 133. Support boss; 14. Second force measuring ring; 141. Second anti-rotation boss; 142. Second cable outlet slot; 15. Bearing bushing; 151. Third mounting slot; 152. Axial clearance; 16. Strain gauge. Detailed Implementation

[0036] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below.

[0037] Figure 5 This is a schematic diagram of the internal structure of a turboprop engine reducer according to a preferred embodiment of the present invention; Figure 6 This is a schematic diagram of the assembly structure of the force measuring device according to a preferred embodiment of the present invention; Figure 7 This is a schematic diagram of the structure of the fifth bearing according to a preferred embodiment of the present invention; Figure 8 This is a schematic diagram of the structure of the first force-measuring ring according to a preferred embodiment of the present invention; Figure 9 This is a schematic diagram of the structure of the fourth bearing according to a preferred embodiment of the present invention; Figure 10 This is a schematic diagram of the structure of the second force-measuring ring according to a preferred embodiment of the present invention; Figure 11 This is a schematic diagram of the bearing bushing according to a preferred embodiment of the present invention; Figure 12 This is a schematic diagram of the propeller thrust transmission path according to a preferred embodiment of the present invention; Figure 13 This is a schematic diagram of the propeller negative thrust transmission path according to a preferred embodiment of the present invention.

[0038] like Figures 5 to 13 As shown, the propeller thrust and pull testing device of this embodiment is applied to a turboprop engine. The turboprop engine includes a reduction gear, which is a spur gear transmission. The reduction gear includes a casing, a power turbine shaft, an input gear 2, a driven gear 3, and a propeller shaft. The input gear 2 is located on the power turbine shaft, and the driven gear 3 is located on the propeller shaft 4 and meshes with the input gear 2. A first bearing 7 and a second bearing 8 are respectively installed between the two ends of the power turbine shaft and the casing. A third bearing 9 for bearing radial force is installed between the rear end of the propeller shaft 4 and the casing. A mounting structure is installed between the front end of the propeller shaft 4 and the casing. A fourth bearing 10 and a fifth bearing 11 are respectively installed between the inner side of the mounting structure and the outer wall of the front end of the propeller shaft 4. The fourth bearing 10... Located between the bottom of the mounting structure and the fifth bearing 11, the fourth bearing 10 has a preset radial clearance with the inner wall of the mounting structure. The fourth bearing 10 is used to bear axial force, and the fifth bearing 11 is used to bear radial force. The testing device includes a first force measuring ring 13 arranged between the fifth bearing 11 and the fourth bearing 10, and a second force measuring ring 14 arranged at the end of the fourth bearing 10 away from the fifth bearing 11. The first force measuring ring 13 is used to test tensile force, and the second force measuring ring 14 is used to test thrust force. The two end faces of the first test ring abut against the outer ring end face of the fourth bearing 10 and the outer ring end face of the fifth bearing 11, respectively. The two end faces of the second test ring abut against the outer ring end face of the fourth bearing 10 and the mounting structure, respectively.

[0039] It should be understood that the power of the reducer is input through the spline 1 of the input gear 2, wherein the input gear 2 has a locking device with the power turbine shaft and is axially limited, as implemented with reference to existing technology. The input gear 2 meshes with the driven gear 3, and the driven gear 3 transmits power to the propeller shaft through the spline 1. The front end of the propeller shaft is connected to the propeller hub through a connecting flange. By outputting the power generated by the engine, the propeller is driven to generate flight power. The two ends of the power turbine shaft are respectively provided with a first bearing 7 and a second bearing 8 between them and the casing. The outer rings of the first bearing 7 and the second bearing 8 both have mounting edges. The inner rings of both are interference-fitted with the input gear 2, and the outer ends are locked by locking nuts 12 provided with the input gear 2. The first bearing 7 and the second bearing 8 are preferably cylindrical roller bearings.

[0040] Understandably, this testing device installs a third bearing 9 at the rear support point of the propeller shaft 4. By setting up an installation structure, a fourth bearing 10 and a fifth bearing 11 are installed at the front support point of the propeller shaft 4. The three support points work together to ensure that the radial force generated during propeller operation is borne solely by the third bearing 9 and the fifth bearing 11 at both the front and rear support points. The fourth bearing 10 only bears the axial force and not the radial force. A first force-measuring ring 13 and a second force-measuring ring 14 are respectively installed at both ends of the outer ring of the fourth bearing 10. When a positive thrust is applied to the propeller, the force is transmitted through the propeller shaft and the inner ring of the fourth bearing 10 to the outer ring of the fourth bearing 10, pressing the first force-measuring ring 13 against the outer ring of the fifth bearing 11. By testing the strain of the first force-measuring ring 13 under load, the axial force borne by the fourth bearing 10 can be obtained. Conversely, when a negative thrust is applied to the propeller, the thrust is transmitted from the propeller shaft to the inner ring of the fourth bearing 10 and then to the outer ring of the fourth bearing 10, pressing the second force measuring ring 14 against the mounting structure. By measuring the strain of the second force measuring ring 14 under load, the axial force borne by the fourth bearing 10 is obtained. Since the reducer is a spur gear transmission structure, no additional axial force is generated during the meshing of the gear pair. Therefore, the axial force borne by the fourth bearing 10 is the propeller thrust / thrust. Compared with the load measurement method of the engine mounting strut system and the method of building a ground test stand, this test device has higher testing accuracy and is not affected by environmental factors and flight airflow. The overall structure is simplified and does not require additional measurement structure construction. It can simultaneously measure the positive and negative thrust of the propeller, with high measurement accuracy and low cost.

[0041] In this embodiment, the mounting structure includes a bearing bushing 15 for being embedded in the end hole at the front end of the casing. A stepped structure 501 is provided at the end hole position at the front end of the casing. The outer wall of the front end of the bearing bushing 15 protrudes to be axially positioned and engaged with the stepped structure 501. That is, the second force measuring ring 14, the fourth bearing 10, the first force measuring ring 13, and the fifth bearing 11 are sequentially installed into the bearing bushing 15. The bottom of the bearing bushing 15 is inserted into the front end hole of the casing until it abuts and engages with the stepped structure 501 in the end hole of the casing for positioning. The structure is simple and reasonable.

[0042] In this embodiment, strain gauges 16 are evenly distributed circumferentially on the first force-measuring ring 13 and the second force-measuring ring 14. The strain gauges 16 are used to test the strain of the force-measuring ring under load and output signals to the testing equipment via signal lines, thereby measuring the thrust and pull of the propeller. Furthermore, the testing device also includes a lead wire structure for leading the signal lines connected to the strain gauges 16 to the outside of the housing. The lead wire structure guides the signal lines connected to the strain gauges 16 through and out of the housing to connect with the testing equipment, avoiding structural interference and wiring chaos.

[0043] In this embodiment, the testing device also includes an anti-rotation structure distributed on the first force measuring ring 13 and the second force measuring ring 14, which is used to limit the circumferential position of the first force measuring ring 13 and the second force measuring ring 14, prevent the first force measuring ring 13 and the second force measuring ring 14 from rotating during operation, and at the same time realize the angular positioning of the first force measuring ring 13 and the second force measuring ring 14 to ensure test accuracy and test stability.

[0044] Specifically, the anti-rotation structure includes a first anti-rotation boss 131 disposed on the end face of the first force-measuring ring 13 facing the fifth bearing 11. The fifth bearing 11 has a first mounting groove 111 for embedding the first anti-rotation boss 131. The anti-rotation structure also includes a second anti-rotation boss 141 disposed on the second force-measuring ring 14. The second anti-rotation boss 141 of the second force-measuring ring 14 extends axially to both ends of the second force-measuring ring 14. The outer ring of the fourth bearing 10 has a second mounting groove 101 for embedding the second anti-rotation boss 141. The bearing bushing 15 has a third mounting groove 151 for cooperating with the second anti-rotation boss 141. The outer end of the fifth bearing 11 has a circumferentially disposed end face for engaging with the front end of the casing. The mounting edge 112 is fitted with the front end of the casing and is connected to the mounting edge 112. This connection fixes the outer ring of the fifth bearing 11 and restricts its circumferential position. The first anti-rotation boss 131 is embedded in the first mounting groove 111, thereby restricting the circumferential position of the first force measuring ring 13 and preventing circumferential rotation during operation. The second anti-rotation boss 141 at one end of the second force measuring ring 14 is embedded in the second mounting groove 101 on the outer ring of the fourth bearing 10, and the second anti-rotation boss 141 at the other end is embedded in the third mounting groove 151 on the bearing bushing 15. This achieves circumferential limitation of the second force measuring ring 14 and the outer ring of the fourth bearing 10, preventing them from rotating circumferentially during operation, avoiding affecting the test accuracy, and ensuring the stability of the test operation.

[0045] In this embodiment, the lead wire structure includes a wire hole 132 formed in the first force-measuring ring 13, a first wire outlet groove 102 formed in the outer wall of the fourth bearing 10, and a second wire outlet groove 142 formed in the outer wall of the second force-measuring ring 14. The second wire outlet groove 142 is set on the second anti-rotation boss 141. The second mounting groove 101 is integrated with the first wire outlet groove 102, that is, the first wire outlet groove 102 is formed axially along the side wall of the fourth bearing 10 based on the position of the second mounting groove 101, so that the structure is integrated and the structure is more concise. Similarly, the second wire outlet groove 142 is formed at the position of the second anti-rotation boss 141, the structure is integrated and the structure is more concise, and the length of the second wire outlet groove 142 is extended, which is more convenient for wire lead wire. In other embodiments, a wire outlet groove structure is also formed on the first force-measuring ring 13 to replace the wire hole 132, and there is no limitation on it.

[0046] In some embodiments, the third bearing 9 and the fifth bearing 11 are cylindrical roller bearings, and the fourth bearing 10 is a four-point contact ball bearing, a deep groove ball bearing, or a spherical roller thrust bearing.

[0047] In this embodiment, the end of the inner ring of the fourth bearing 10 away from the fifth bearing 11 abuts against the end of the driven gear 3 or against the shoulder of the propeller shaft 4, and the bottom of the bearing bush 15 and the end of the outer ring of the fourth bearing 10 away from the fifth bearing 11 form a preset axial distance so that the second force measuring ring 14 and the bottom of the bearing bush 15 have an axial gap 152, in order to compensate for manufacturing errors and thermal deformation, prevent the force measuring ring from getting stuck in the assembly state, and affect the test accuracy. At the same time, since the outer ring of the fourth bearing 10 and the inner wall of the bearing bush 15 have a radial gap and no radial fit, the outer ring of the fourth bearing 10 has an axial floating space during operation. When subjected to thrust, the outer ring of the fourth bearing 10 drives the second force measuring ring 14 to abut against the bottom of the bearing bush 15, thereby realizing the transmission of force and acting on the second force measuring ring 14.

[0048] It is understandable that the first force-measuring ring 13 has support bosses 133 evenly distributed circumferentially at one end facing the fourth bearing 10, which are used to abut against the fourth bearing 10 after assembly to achieve positioning; the size of the second force-measuring ring 14 matches the size of the outer ring of the fourth bearing 10 to accommodate the axial floating of the outer ring of the fourth bearing 10.

[0049] It should be noted that the end of the fourth bearing 10 furthest from the fifth bearing 11 preferably abuts against the end of the driven gear 3, while the end of the fifth bearing 11 furthest from the fourth bearing 10 abuts against the shoulder of the propeller shaft 4. Specifically, the gearbox is divided into a front gearbox 5 and a rear gearbox 6. The assembly method of this reducer is as follows: from the rear end of the propeller shaft 4, the fifth bearing 11, the first force-measuring ring 13, the fourth bearing 10, the second force-measuring ring 14, the bearing bushing 15, the front gearbox 5, the driven gear 3, the third bearing 9, the lock nut 12, and the rear gearbox 6 are installed in sequence, and the fifth bearing 11 is then installed. The first force-measuring ring 13 is installed on the front shoulder of the propeller shaft 4, and the first anti-rotation boss 131 of the first force-measuring ring 13 is aligned and embedded into the first mounting groove 111 of the fifth bearing 11. Then, the fourth bearing 10 is installed so that it abuts against the support boss 133 of the first force-measuring ring 13. The second force-measuring ring 14 is installed so that one end of the second anti-rotation boss 141 is embedded into the second mounting groove 101. The bearing bushing 15 is installed so that the third mounting groove 151 and the other end of the second anti-rotation boss are engaged. The driven gear 3 and the third bearing 9 are installed and then locked by the lock nut 12. The rear casing 6 is then installed to complete the assembly.

[0050] The assembly of the input gear 2, the first bearing 7, and the second bearing 8 is carried out with reference to existing assembly processes, which are not described in the above assembly process.

[0051] In the description of this invention, it should be noted that the terms "upper", "lower", "front", "rear", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0052] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0053] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A propeller thrust and pull testing device, applied to a turboprop engine, the turboprop engine including a reducer, the reducer including a casing, a power turbine shaft, an input gear (2), a driven gear (3), and a propeller shaft, the input gear (2) being disposed on the power turbine shaft, the driven gear (3) being disposed on the propeller shaft (4) and meshing with the input gear (2), a first bearing (7) and a second bearing (8) being respectively disposed between the two ends of the power turbine shaft and the casing, characterized in that, A third bearing (9) for bearing radial force is provided between the rear end of the propeller shaft (4) and the casing. A mounting structure is provided between the front end of the propeller shaft (4) and the casing. The mounting structure includes a bearing bushing (15) for fitting into the end hole of the front end of the casing. A fourth bearing (10) and a fifth bearing (11) are respectively provided between the inner side of the mounting structure and the outer wall of the front end of the propeller shaft (4). The fourth bearing (10) is located between the bottom of the mounting structure and the fifth bearing (11). There is a preset radial clearance between the fourth bearing (10) and the inner wall of the mounting structure. The fourth bearing (10) is used to bear axial force, and the fifth bearing (11) is used to bear radial force. The testing device includes a bearing bushing (9) arranged on the fifth bearing (9). 11) and the first force measuring ring (13) between the fourth bearing (10) and the second force measuring ring (14) disposed at the end of the fourth bearing (10) away from the fifth bearing (11), the first force measuring ring (13) is used to test the tension, and the second force measuring ring (14) is used to test the thrust; the end of the inner ring of the fourth bearing (10) away from the fifth bearing (11) abuts against the end of the driven gear (3) or abuts against the shoulder of the propeller shaft (4) and the bottom of the bearing bush (15) and the end of the outer ring of the fourth bearing (10) away from the fifth bearing (11) form a preset axial distance so that the second force measuring ring (14) and the bottom of the bearing bush (15) have an axial gap (152).

2. The propeller thrust and pull testing device according to claim 1, characterized in that, The front end of the casing is provided with a stepped structure (501), and the bearing bushing (15) is axially positioned and engaged with the stepped structure (501).

3. The propeller thrust and pull testing device according to claim 2, characterized in that, The first force measuring ring (13) is provided with strain gauges (16) evenly distributed in the circumferential direction, and the second force measuring ring (14) is provided with strain gauges (16) evenly distributed in the circumferential direction.

4. The propeller thrust and pull testing device according to claim 3, characterized in that, The testing device also includes a lead wire structure for leading the signal wire connected to the strain gauge (16) to the outside of the housing.

5. The propeller thrust and pull testing device according to claim 4, characterized in that, The testing device also includes an anti-rotation structure distributed on the first force measuring ring (13) and the second force measuring ring (14) to limit the circumferential position of the first force measuring ring (13) and the second force measuring ring (14).

6. The propeller thrust and pull testing device according to claim 5, characterized in that, The anti-rotation structure includes a first anti-rotation boss (131) disposed on the end face of the first force measuring ring (13) facing the fifth bearing (11). The fifth bearing (11) is provided with a first mounting groove (111) for embedding the first anti-rotation boss (131). The anti-rotation structure also includes a second anti-rotation boss (141) disposed circumferentially on the second force measuring ring (14). The second anti-rotation boss (141) extends axially to both ends based on the second force measuring ring (14). The outer ring of the fourth bearing (10) is provided with a second mounting groove (101) for embedding the second anti-rotation boss (141). The bearing bushing (15) is provided with a third mounting groove (151) for cooperating with the second anti-rotation boss (141).

7. The propeller thrust and pull testing device according to claim 6, characterized in that, The lead wire structure includes a wire hole (132) opened in the first force measuring ring (13), a first wire outlet groove (102) opened in the outer wall of the fourth bearing (10), and a second wire outlet groove (142) disposed in the outer wall of the second force measuring ring (14). The second wire outlet groove (142) is disposed in the second anti-rotation boss (141), and the second mounting groove (101) is integrated with the first wire outlet groove (102).

8. The propeller thrust and pull testing device according to claim 1, characterized in that, The outer end of the fifth bearing (11) is provided with a mounting edge (112) for engaging with the end face of the front end of the casing.

9. The propeller thrust and pull testing device according to any one of claims 1-8, characterized in that, The third bearing (9) and the fifth bearing (11) are cylindrical roller bearings, and the fourth bearing (10) is a four-point contact ball bearing, a deep groove ball bearing, or a spherical roller thrust bearing.

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